It is the only cranial nerve that exits from the dorsal (rear) aspect of the brainstem. It innervates a muscle, the superior oblique muscle, on the opposite side (contralateral) from its nucleus. The trochlear nerve decussates within the brainstem before emerging on the contralateral side of the brainstem (at the level of the inferior colliculus).

2023年7月15日 · The trochlear nerve is the fourth cranial nerve (CN IV) and one of the ocular motor nerves that controls eye movement. The trochlear nerve, while the smallest of the cranial nerves, has the longest intracranial course as it is the …

What is the trochlear nerve? Your trochlear nerve, also known as the cranial nerve 4 or CN IV, is a motor (movement) nerve that sends signals from your brain to one of the muscles that control eye movement. You have two trochlear nerves — one for …

2023年10月30日 · The trochlear nerve (CN IV) arises from the trochlear nucleus located within the periaqueductal gray substance of the midbrain and emerges on the dorsal midbrain caudal to the inferior colliculus. It then crosses the midline, before passing anteriorly around the contralateral side of the brainstem.

2025年2月10日 · Motor Function. The trochlear nerve innervates a single muscle – the superior oblique, which is a muscle of oculomotion. As the fibres from the trochlear nucleus cross in the midbrain before they exit, the trochlear neurones innervate the contralateral superior oblique.

Function [edit | edit source] The trochlear nerve transmits general somatic efferent impulses, which synapse in the skeletal fibers of the superior oblique muscle. The superior oblique muscles allow for depression, abduction, and medial rotation (intortion) of the eyeball.

2019年4月10日 · CN IV is the trochlear nerve. It provides general somatic efferent to the extraocular superior oblique muscle. It assists in depressing and abducting the eye. It connects to the midbrain and is the only cranial nerve to leave the brainstem posteriorly. It passes through the superior orbital fissure of the skull. Sinnatamby, C. S. (2011).

2017年5月22日 · The trochlear nerve or the fourth cranial nerve (CN IV) arises from the dorsal aspect of the mesencephalon. Its anatomical course, function and pathology are described.

2023年7月15日 · The trochlear nerve is the fourth cranial nerve (CN IV) and one of the ocular motor nerves that controls eye movement. The trochlear nerve, while the smallest of the cranial nerves, has the longest intracranial course as it is the …

2024年12月23日 · The trochlear nerve is the fourth (CN IV) and thinnest cranial nerve. It exits the midbrain posteriorly, eventually passes into the cavernous sinus and into the orbit where it supplies superior oblique muscle with motor fibers (TA: nervus trochlearis or nervus cranialis IV).